When it comes to talking a big game, no one does it better than the North Koreans.

Just this week, Pyongyang vowed to turn Seoul, the capital of archrival South Korea, into a "sea of fire," promised to launch a "pre-emptive strike on the headquarters of the aggressors" (read: the United States) and called on its army to "annihilate the enemy."

Most experts and Korea watchers believe the latest rhetoric is just the usual propaganda engine cranked up to 11. But if North Korea should suddenly move to make its threats a reality, how bad could it be? Are the North's nuclear bombs and ballistic missiles push-button ready? What about its massive tank and artillery forces?

By contrast, South Korea has just 460 jets, but most are combat ready. Likewise, the North has a nearly 2-to-1 numerical advantage in tanks (4,200 to South Korea's 2,400), but according to Reuters, Seoul's armor is "more modern and better maintained."

A Large Military With Limited Capabilities

Jennifer Lind, an associate professor at Dartmouth College, says a big part of the reason that Pyongyang has been so keen to acquire nuclear weapons and ballistic missiles is precisely because its 1.1 million-strong army, the world's fourth largest, is a paper tiger.

She points to a detailed analysis of North Korea's conventional capability done by some of her colleagues in 1995 that showed Pyongyang was "pretty hopelessly outgunned" by the U.S. and South Korean forces.

"They had completely inferior tanks and artillery," she says. "Their air force was so antiquated that it would have been shot out of the sky in the first few hours of a conflict."

Instead of improving, the situation deteriorated in the intervening 18 years, Lind says, likely because of North Korea's isolation and its long-running food shortages.

"As bleak as things looked back then, I think they've only gotten worse," she says.

'A Cold War Relic'

Victor Cha, who holds the Korea Chair at the Center for Strategic and International Studies, agrees that North Korea's conventional military is a Cold War relic — "something out of the '50s, '60s or '70s," he says.

Pyongyang also commands a formidable artillery force numbering some 12,000 guns that some fear it would use as an opening gambit in a war with South Korea to shell Seoul, which lies only about 20 miles from the tense demilitarized zone that separates the two countries.

Cha also thinks many experts are not taking the nuclear and missile threats from North Korea seriously enough.

In its latest test, the North claims to have trialed a higher yield device — a claim that makes sense if it's trying to perfect a deliverable warhead.

"The bottom line is that we just don't know where Pyongyang's capabilities lie," Cha says. "These tests might represent lighter and smaller weapons."

"The North could be lying about that, but then again, maybe they aren't," he says.

Simply possessing a static nuclear device, however, is not the same as having one that can be launched atop a missile, Lind says.

North Korea's claims aside, the physical size of the device used in the most recent test seem likely to be "way too big" to launch on a missile or even deliver, in any practical sense, by airplane, she says.

George Lopez, a political science professor at the University of Notre Dame, is more emphatic. Even if the North had a small, deliverable weapon, he says, "I think most of the bets are that they do not have the capability to reliably reach a target."

"They don't seem to have the booster they need to get a workable weapon to land where they want it to," Lopez says.

"Could they build something, load it on an airplane and drop it over South Korea? Maybe, but it would pretty difficult, probably impossible."